The present invention relates to connectors for conduits, and more particularly to improvements in connectors of the type wherein two discrete valves assume closed or sealing positions to prevent a fluid from flowing into or from the conduits in automatic response to separation of the conduits from each other. One or more connectors which embody the present invention can be used with advantage in conduits which connect the interelectrode gas gap of an ionography imaging chamber in X-ray apparatus with one or more sources of gaseous media, e.g., with sources of high Z gases. Imaging chambers and X-ray apparatus of the type which can utilize the improved connector or connectors are disclosed in the commonly owned copending application Ser. No. 720,577 entitled "Ionography Imaging Chamber" filed Sept. 7, 1976 by Jurgen Muller et al. The interelectrode gas ga of an ionography imaging chamber must be maintained at an elevated pressure (e.g., 6-20 atmospheres) during imaging of an object onto an insulating receiver medium, and the gap is filled with a high Z gas (normally Xenon or krypton) which must be evacuated from the gap prior to withdrawal of a freshly exposed receiver medium. The noble gas is expensive and, therefore, the conduits for such gas must be sealed from the atmosphere not only when they connect the gap with a source of noble gas but also when the customary couplings in such conduits must be disengaged for any one of a variety of reasons. The presently known connectors or couplings in such conduits are not sufficiently reliable, i.e., leakage of expensive gases is quite pronounced not only when the couplings are engaged but also when the connection between the conduits, which are normally coupled to each other, is terminated or interrupted.